What is dry age-related macular degeneration (AMD)?

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Dry AMD is a disease of the macula, which is the part of the eye that sits near the center of the retina. This part of the eye typically allows for high resolution color vision. However, dry AMD causes the macula’s light-sensitive cells to die, making it difficult for a person to see clearly.

Blurry vision is often the first sign of AMD. Eventually, a person loses their central field of vision. In dry AMD, these changes usually occur slowly. In wet AMD, leaky blood vessels develop under the macula and speed up the damage.

Regular comprehensive eye exams can detect macular degeneration before it causes vision changes. Appropriate treatment can help slow down vision loss.

Doctors divide dry AMD into three stages: early, intermediate, and late. Each stage comes with different symptoms:

• Early stage: At this stage a person does not experience any AMD symptoms.
• Intermediate stage: People may notice mild blurriness in their central vision or difficulty seeing in low light. However, even at this stage, not everyone has symptoms.
• Late stage: At the late stage, people can have a variety of symptoms, including:
  • one or more blurred or blank areas toward the center of their vision, which increase over time
  • straight lines appearing wavy or wonky
  • colors appearing less bright

If a person notices that straight lines look wavy, they should seek urgent medical attention from an eye doctor, as this is a warning sign of late AMD.

Doctors do not fully understand the causes of AMD, but they know that people ages 55 years and older are more likely to develop the disease. People may have a higher risk of AMD if they:

• Smoke: People who smoke are up to four times more likely to develop AMD. As the retina and macula consume large amounts of oxygen, anything that interferes with oxygen delivery, such as smoking, may affect eye health.
• Have high blood pressure: Similarly, high blood pressure can restrict blood flow to the eye and reduce oxygen supply. This may increase a person’s risk of developing AMD.
• Have a family history of AMD: If someone in a person’s immediate family has AMD, the person is more at risk.
• Have obesity: People who have a body mass index (BMI) of 30 or higher are more likely to develop AMD and other degenerative eye conditions.
• Have an unbalanced diet: If a person consumes large amounts of fat, cholesterol, and refined carbohydrates and does not consume enough leafy green vegetables and antioxidants, they may be more likely to develop AMD.
• Are white: White people have a higher risk of AMD than people of other racial groups.
• Are female: Females are more likely than males to develop AMD. This could be because females live longer, on average, so they have more time to develop the disease.

To diagnose AMD, an ophthalmologist performs a comprehensive eye exam, including the following:

• Eye chart test: This test measures a person’s sight from various distances.
• Autofluorescence: A doctor may use autofluorescence photos to examine the retina and measure disease progression in people with advanced dry AMD. Autofluorescence allows doctors to monitor the retinal pigment epithelium, the retina’s deepest layer.
• Dilated eye exam: During this test, a doctor uses special eye drops to dilate the pupils. This allows them to examine the retina for disease and see any optic nerve damage.
• Fundoscopy or ophthalmoscopy: These tests involve shining a beam of bright light into the dilated eye to check for problems in the retina, the blood vessels, the area where the optic nerve connects to the retina, and the choroid. The choroid is a thin layer of tissue connecting blood vessels and nerves to other parts of the eye.
• Fundus photography: The doctor may use a specialized camera to photograph the back of the eye and check for signs of disease. This allows the doctor to measure changes in the eyes between visits.
• Optical coherence tomography (OCT): This noninvasive technique captures cross-sectional images of the retina, allowing the doctor to measure the thickness. OCT helps doctors identify thinning areas and can also help them assess treatment responses.

Doctors can detect the signs of AMD during a regular eye test. People can also see an ophthalmologist if they notice any changes in their vision.

There is no cure for AMD, but treatment can slow the progression of the disease. It is important to begin treatment as early as possible. Once AMD reaches the advanced stage, a doctor cannot prevent further vision impairment.

Early treatment for dry AMD involves making lifestyle changes to reduce damage to the retina and monitoring for vision changes that could indicate disease progression. Early treatment may involve the following changes, if applicable:

• quitting smoking
• adopting a balanced diet high in antioxidants
• getting regular exercise
• managing high blood pressure
• attending regular appointments with an ophthalmologist

A doctor may recommend that a person use an Amsler grid at home. This tool can help people tell whether their symptoms are changing. If AMD is progressing, the grid lines will start to appear curved.

For intermediate dry AMD, the main treatment is a special dietary supplement known as the Age-Related Eye Disease Studies 2 (AREDS2) supplement. AREDS2 supplements may slow the progression from intermediate AMD to late AMD.

The AREDS2 supplement contains large amounts of antioxidants, vitamins, zinc, and copper. For this reason, it can cause side effects or interact with any medications a person takes or other conditions they have. A person can talk with their doctor about whether AREDS2 is right for them.

Recently, the Food and Drug Administration (FDA) also approved several medications, such as pegcetacoplan for treating geographic atrophy, an advanced form of dry macular degeneration.

A treatment option for late stage dry AMD is the use of an implantable miniature telescope (IMT). This involves a procedure in which surgeons place a tiny telescope in one eye. The eye with the IMT then provides central vision while the other provides peripheral vision. People who undergo this procedure need training to use the device.

In addition to treatments that target AMD itself, people with the disease sometimes have to adapt to changes in their vision, such as blurriness. The National Eye Institute refers to this as low vision.

The type of vision changes AMD causes can make it difficult to read, drive, and distinguish colors. However, there are ways to make tasks easier. People with minor vision loss may find it helpful to try:

• using brighter lights
• using a magnifying glass to read
• wearing anti-glare sunglasses

Vision rehabilitation is a type of support that people with more advanced vision loss can receive. It helps people learn how to live with changes to their vision, such as by adapting their home or using visual aids. A person can ask an ophthalmologist about this type of support.

People can also find resources on adjusting to vision loss on the website of the American Foundation for the Blind.

In 10–15% of people with dry AMD, the disease progresses to the wet form. Wet AMD is more serious and can lead to severe vision loss, as the symptoms appear and worsen rapidly.

In addition to nutritional supplements, doctors have other treatment options to prevent further vision loss in wet AMD. These include drugs that a doctor can inject into the eye and photodynamic therapy, which is a form of laser treatment.

Dry AMD is a progressive disease in which light-sensitive cells on the macula begin to die. There is no cure, but early detection and treatment can delay vision loss. In some people, treatment can help stop the disease from progressing once it reaches the intermediate stage.

Frequent eye checkups and monitoring are essential in managing dry AMD. People may also find it helpful to get support in adapting to visual changes such as blurriness or loss of central vision. A person can speak with an ophthalmologist about any concerns.